ABSTRACT
The effect of alpha and beta adrenergic blockers, phentolamine (PH) and propranolol (PR), on the anorexia induced by intraperitoneal (i.p.) adrenaline (A) was studied in 24 h-fasting male and female adult Wistar rats. I.p. PH elicited a small but significant increase in food intake in both males and females. The combination of PH + PR completely blocked the anorexia elicited by i.p. A in both males and females. In females, PH and PR alone partially blocked A-induced anorexia. In males, PH had no significant effect on A-induced anorexia but PR blocked it completely. It was concluded that the relative participation of alpha and beta adrenergic receptors in A-induced anorexia seems to depend on the sex of the rat, at least for the doses used in the present study: in females, alpha and beta actions seem to be approximately equal, while in males the beta is predominant.
